kernel-5.4: bump to 5.4.102 and refresh patches

5.4.102 backported a lot of stuff that our WireGuard backport already
did, in addition to other patches we had, so those patches were
removed from that part of the series. In the process other patches were
refreshed or reworked to account for upstream changes.

This commit involved `update_kernel.sh -v -u 5.4`.

Cc: John Audia <graysky@archlinux.us>
Cc: David Bauer <mail@david-bauer.net>
Cc: Petr Štetiar <ynezz@true.cz>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>

1 files changed, 88 insertions, 0 deletions

diff --git a/target/linux/generic/backport-5.4/080-wireguard-0101-wireguard-send-receive-use-explicit-unlikely-branch-.patch b/target/linux/generic/backport-5.4/080-wireguard-0101-wireguard-send-receive-use-explicit-unlikely-branch-.patch
new file mode 100644
index 0000000000..900e2f2350
--- /dev/null
+++ b/target/linux/generic/backport-5.4/080-wireguard-0101-wireguard-send-receive-use-explicit-unlikely-branch-.patch
@@ -0,0 +1,88 @@
+From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
+From: "Jason A. Donenfeld" <Jason@zx2c4.com>
+Date: Wed, 6 May 2020 15:33:06 -0600
+Subject: [PATCH] wireguard: send/receive: use explicit unlikely branch instead
+ of implicit coalescing
+
+commit 243f2148937adc72bcaaa590d482d599c936efde upstream.
+
+It's very unlikely that send will become true. It's nearly always false
+between 0 and 120 seconds of a session, and in most cases becomes true
+only between 120 and 121 seconds before becoming false again. So,
+unlikely(send) is clearly the right option here.
+
+What happened before was that we had this complex boolean expression
+with multiple likely and unlikely clauses nested. Since this is
+evaluated left-to-right anyway, the whole thing got converted to
+unlikely. So, we can clean this up to better represent what's going on.
+
+The generated code is the same.
+
+Suggested-by: Sultan Alsawaf <sultan@kerneltoast.com>
+Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
+Signed-off-by: David S. Miller <davem@davemloft.net>
+Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
+---
+ drivers/net/wireguard/receive.c | 13 ++++++-------
+ drivers/net/wireguard/send.c    | 15 ++++++---------
+ 2 files changed, 12 insertions(+), 16 deletions(-)
+
+--- a/drivers/net/wireguard/receive.c
++++ b/drivers/net/wireguard/receive.c
+@@ -226,21 +226,20 @@ void wg_packet_handshake_receive_worker(
+ static void keep_key_fresh(struct wg_peer *peer)
+ {
+ 	struct noise_keypair *keypair;
+-	bool send = false;
++	bool send;
+ 
+ 	if (peer->sent_lastminute_handshake)
+ 		return;
+ 
+ 	rcu_read_lock_bh();
+ 	keypair = rcu_dereference_bh(peer->keypairs.current_keypair);
+-	if (likely(keypair && READ_ONCE(keypair->sending.is_valid)) &&
+-	    keypair->i_am_the_initiator &&
+-	    unlikely(wg_birthdate_has_expired(keypair->sending.birthdate,
+-			REJECT_AFTER_TIME - KEEPALIVE_TIMEOUT - REKEY_TIMEOUT)))
+-		send = true;
++	send = keypair && READ_ONCE(keypair->sending.is_valid) &&
++	       keypair->i_am_the_initiator &&
++	       wg_birthdate_has_expired(keypair->sending.birthdate,
++			REJECT_AFTER_TIME - KEEPALIVE_TIMEOUT - REKEY_TIMEOUT);
+ 	rcu_read_unlock_bh();
+ 
+-	if (send) {
++	if (unlikely(send)) {
+ 		peer->sent_lastminute_handshake = true;
+ 		wg_packet_send_queued_handshake_initiation(peer, false);
+ 	}
+--- a/drivers/net/wireguard/send.c
++++ b/drivers/net/wireguard/send.c
+@@ -124,20 +124,17 @@ void wg_packet_send_handshake_cookie(str
+ static void keep_key_fresh(struct wg_peer *peer)
+ {
+ 	struct noise_keypair *keypair;
+-	bool send = false;
++	bool send;
+ 
+ 	rcu_read_lock_bh();
+ 	keypair = rcu_dereference_bh(peer->keypairs.current_keypair);
+-	if (likely(keypair && READ_ONCE(keypair->sending.is_valid)) &&
+-	    (unlikely(atomic64_read(&keypair->sending.counter.counter) >
+-		      REKEY_AFTER_MESSAGES) ||
+-	     (keypair->i_am_the_initiator &&
+-	      unlikely(wg_birthdate_has_expired(keypair->sending.birthdate,
+-						REKEY_AFTER_TIME)))))
+-		send = true;
++	send = keypair && READ_ONCE(keypair->sending.is_valid) &&
++	       (atomic64_read(&keypair->sending.counter.counter) > REKEY_AFTER_MESSAGES ||
++		(keypair->i_am_the_initiator &&
++		 wg_birthdate_has_expired(keypair->sending.birthdate, REKEY_AFTER_TIME)));
+ 	rcu_read_unlock_bh();
+ 
+-	if (send)
++	if (unlikely(send))
+ 		wg_packet_send_queued_handshake_initiation(peer, false);
+ }
+